How long can you live without food?
A healthy person can usually survive several weeks without food, roughly one to two months, as long as they drink water. Survival depends on body fat, health and conditions.
When food runs out, the body first uses stored sugar, then fat, and finally breaks down muscle for energy. People with more body fat can last longer. Without water, though, survival drops to only a few days.
Historical records of hunger strikes show that some people lasted roughly 45 to 70 days without food before dying. Long fasting causes severe weakness, vitamin and mineral shortages, damage to the heart and other organs, and can be fatal.
Refeeding risks
After a long period without food, eating again must be done carefully under medical supervision. Sudden refeeding can cause dangerous shifts in salts and fluids in the body, a condition called refeeding syndrome.
The body also needs vitamins and minerals, not just calories. Long periods without them can cause problems such as scurvy, a disease caused by lack of vitamin C that once affected sailors on long voyages.
Did You Know?
Medically supervised fasting programs are carefully monitored, and doctors warn against long fasts without professional guidance.
This answer is general information, not medical advice. For a personal health question, talk to a doctor.